Washington -LRB- CNN -RRB- -- Rep. Charlie Rangel temporarily stepped down as chairman of the House Ways and Means Committee on Wednesday , a decision forced by a growing storm of ethics controversies threatening the longtime congressman .

The 20-term New York Democrat told reporters he had submitted a letter to House Speaker Nancy Pelosi requesting a temporary leave of absence until a broad-reaching House ethics committee investigation concludes .

`` In order to avoid my colleagues ' having to defend me during their elections , I have this morning sent a letter to Speaker Pelosi asking her to grant me a leave of absence until such time as the ethics committee completes its work , '' Rangel said Wednesday .

In a statement , Pelosi said she had accepted Rangel 's request and praised the congressman for `` his decades of leadership on jobs , health care and the most significant economic issues of the day . ''

Read Rangel 's letter to Pelosi

The night before Rangel said he had no plans to step aside from his powerful post . The Ways and Means Committee is responsible for drafting the nation 's tax policies .

Rangel is being investigated for , among other things , failing to pay taxes on a home in the Dominican Republic . The congressman also has admitted failing to report several hundred thousand dollars in assets on federal disclosure forms .

In addition , he is under scrutiny for the purported misuse of a rent-controlled apartment for political purposes , as well as for allegedly preserving tax benefits for an oil-drilling company in exchange for donations to a project he supported at the City College of New York .

Rangel was formally admonished Friday by the House ethics committee for violating rules on receiving gifts . Specifically , the committee found that Rangel violated House gift rules by accepting reimbursement payments for travel to conferences in the Caribbean in 2007 and 2008 .

Rangel 's staff , according to the committee , knew that corporations had given money to the Carib News , which sponsored the events . That fact had not been divulged to the ethics committee when Rangel asked for and received approval to attend the trips , according to the committee 's report . The committee found that while Rangel did not know about the contributions , he was nevertheless responsible .

A source told CNN on Tuesday that if Rangel stepped aside , senior Ways and Means Democrat Pete Stark would take over as the committee 's chairman `` on a temporary basis . ''

House Republicans plan to introduce a resolution Wednesday calling on Rangel to permanently step down and again force House Democrats to go on record defending him . They issued a statement after Rangel 's announcement , calling his decision to temporarily step aside an `` embarrassing episode '' for the Democratic majority .

`` Nancy Pelosi 's promise to run the ` most ethical Congress in history ' has been reduced to a punch line , and as a result she is presiding over a caucus in chaos , '' said GOP spokesman Ken Spain . `` The Democrats -- under Speaker Pelosi 's leadership -- are incapable of leading the United States Congress . ''

House Democrats have blocked previous GOP resolutions on the House floor , but several Democrats in competitive districts have come out publicly in recent days , saying they thought it was time for Rangel to step down .

Rangel is a founding member of the Congressional Black Caucus , which has 42 members in the House .

CNN 's Brianna Keilar and Deirdre Walsh contributed to this report

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NEW : Republicans plan to call for Rep. Charlie Rangel to step aside permanently

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Rangel investigated for failing to pay taxes on Dominican Republic home

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House ethics committee admonished him for violating rules on receiving gifts

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House Ways and Means Committee responsible for drafting nation 's tax policies